A very interesting article about the sounds of No Man's Sky. I guess I never thought that while every planet/animal/ship would be mathematically generated... all of the sounds would have to be as well.
Our brains are very adept at detecting patterns, and the reason synthetic voices typically sound artificial is that they are carried on sound waves that have a regular frequency: unvarying up-down-up-down modulations that are unmistakably inorganic. White suspected that if he built digital vocal chords (stimulated by columns of mathematically simulated air) the system would achieve naturalism. “The first results were a bit like the squeaker out of a dog toy,” he said, which wasn’t surprising: blow through the mouthpiece of a clarinet without the instrument, and the effect is similar. White then added a digital version of the pharynx, which sits behind the mouth and nasal cavity; it served as a resonator, amplifying sounds produced by the vocal chords, but also altering their texture. The squeaks became elongated. He called this the system’s “trumpety-chicken-duck-whale-car-horn phase.” By the end of January, several weeks after he had started programming, he added a digital mouth—the final component necessary for a rudimentary virtual vocal tract. Then he set about giving his creation a voice.
Every vowel is defined by a narrow band of frequencies, known as a formant, which are created by the vocal tract as a whole—the way sound resonates throughout all its parts. White found a paper from 1962, titled “A Study of Formants of the Pure Vowels of British English.” The paper, based on recordings of twenty-five male subjects, contained a table of the relevant data. Late one night, alone in his Edinburgh studio, he copied the values for a vowel labeled “/a/ hard” and plugged them into his system. The digital resonance that White had created—with vocal chords, pharynx, and mouth all affecting each other—caused the utterance to take on human character, and the result was a blood-curdling scream. The voice broke, twisted, and grew horse during moments of high intensity. White gave me an MP3 of it, and I later played it for two people without telling them what it was. Both thought it came from an animal; one wondered if it was a person being tortured, and the other wondered if it was a goat. White recalled, “Two o’clock in the morning, headsets in, and the thing went ‘Aaaaahhhhh.’ I was sweating because it was so scary. But I was also like, This is working!”
Raising the iPad, Weir said, “It feels like an instrument.” He offered to play it. Drawing his finger across the screen, he nudged the lever bars to indicate attributes like body mass, aggressiveness, windpipe length, wetness, screechiness, harshness. (The software makes sounds based on roughly a hundred different parameters.) Then, while moving his thumbs across two graphical boxes on the iPad—one labelled “vowel map,” the other “pitch”—and simultaneously twisting the device in space, he generated a vocalization. The iPad’s physical movement determined the energy behind the utterance: the arc of the motion shaping the sound’s arc.
Out came a tired, yawn-like rumbling, the deep grunt of a lumbering multi-ton herbivore. “I can change the size,” Weir said. He tinkered with the iPad, and moved it differently, and the vocalization’s over-all frequency become higher; the texture became rougher and wetter. After a few seconds, Weir gave it an upturn in pitch and intensity. The sound resembled the mating call of some tropical species.